Analysis of Work Quality Indicators of Single-Server Computer Networks Providing Queued Service on First and Second Priority

Abstract

- It has been shown that in a single-channel non-priority network with a limited queue, increasing the number of waiting spots has an insignificant effect on the probability of failures under low loads; however, as the loads increase with the same number of waiting spots, the probability of failures sharply rises.

- Method for calculating the quality indicators of node functioning in computer networks with prioritized servicing of incoming packet streams;

- An analytical model of a single-channel multi-node computer network with a limited queue and absolute priority, dependent on the number of network nodes, the number of waiting places in individual nodes, and the loads of the first and second priorities, has been developed. Application software packages have been created, which were used to perform calculations and build dependencies of failure probabilities for various values of individual priority loads, the number of network nodes, and the number of waiting places in individual nodes. It has been determined that in single-channel multi-node networks with limited queues and absolute priority, under the same load conditions, the quality of service for requests significantly deteriorates with an increasing number of nodes.

    To ensure the desired level of service quality for requests, it is necessary to increase the number of waiting spots at individual network nodes. An analysis of a single-channel multi-node network with a limited queue and absolute priority shows that the quality of service for requests in such networks heavily depends on the load of individual priorities.

    The provided numerical calculations and constructed dependency graphs make it possible to determine the required quality of operation of a specific computer network with a given number of nodes, the number of waiting places in specific nodes, and the values of first and second priority loads.